Adaptive Finite-Time Dynamic Output-Feedback FTC Design for MIMO Nonlinear Systems With Actuator and Sensor Faults

Abstract

This paper investigates the problem of the finite-time fault-tolerant control for multipleinputs multiple-outputs nonlinear systems. The controlled systems contain the unmeasurable states, unknown parameters and possible actuator, and sensor faults. First, a new dynamic output-feedback control strategy (high-gain K-filter observer with new dynamic gain update rule) is designed, which can simultaneously estimate the unmeasurable states and unknown parameters. Then, by employing a cubic absolute-value Lyapunov function and our designed dynamic high-gain K-filter observer, both actuator and sensor faults can be compensated concurrently. The controller design utilizes the adaptive backstepping approach and the stability analysis employs the Lyapunov function stability theory and the finite-time stability criterion. It is proved that by using the proposed method, all the signals in the closed-loop systems are semi-global practical finite-time stable, and also the tracking errors can converge to a sufficiently small neighborhood of zero in finite time. Final, simulation results verify the effectiveness of the proposed method.

Keywords

• MIMO nonlinear systems with parameter uncertainties
• actuator and sensor fault
• high gain K-filter observer
• fault-tolerant control
• adaptive backstepping control